A Seoul appellate court acquitted a reporter on Friday of falsely claiming that the younger brother of President Park Geun-hye may have been behind the murder of his nephew.

In 2013, a lower court had cleared Joo Jin-woo, a reporter of the monthly news magazine Sisa IN, of charges that he spread false information about Park Ji-man in an article published in December 2012.

At the height of President Park's presidential campaign, Joo's article revisited a 2011 case in which the body of Park's nephew was found on a hiking trail near Mount Bukhan in northern Seoul.

Just three kilometers from the scene, another one of her nephews was found hanging from a tree.

Police concluded that one of the nephews had murdered the other after getting into a financial dispute, and then hung himself.

But Joo alleged that Park Ji-man may have ordered the murder, citing a legal dispute between Ji-man and his brother-in-law, who is the father of the two nephews.

Joo also faced charges that he slandered the president's late father, former President Park Chung-hee, during a book event in 2010.

Upholding a lower court ruling, the Seoul High Court said Joo was not guilty of spreading false information since he'd tried his best to uncover the truth behind the murder.

"Considering the premise of his article and his show, he didn't knowingly spread false rumors," Judge Kim Sang-hwan said in a ruling.

The judge also said Joo's statement at the book event did not constitute libel, citing freedom of speech.

"He was simply expressing his disapproval of the former president's economic policy," the judge said.

Joo gained national fame as a co-host of a popular podcast show, which started in 2011 and regularly stirred up allegations of wrongdoing by notable politicians, business executives and religious leaders. The show was suspended after December's presidential election. (Yonhap)